Swagger UI overrides accept header parameter

[lakmali]

We are using swagger 2.1.0.

We need to dynamically send different accept header values. For that we added this new parameter accept. But Swagger UI sends application/json as the accept header all the time. We tried setting "produces" with multiple values. But for that swagger UI sends the first value as the accept header.

Is there any workaround for this?

 get:
      x-auth-type: "Application & Application User"
      x-throttling-tier: Unlimited
      produces:
        - "application/xml,application/json"
      parameters:
        - name: id
          allowMultiple: false
          type: string
          required: true
          in: path
        - name: Accept
          type: string
          required: false
          in: header
      responses:
        "200": {}

[webron]

You can't override the Accept header and you have to use produces for it.

Your definition is malformed, and not parsed properly by the UI.
There are two issues:

1. The produces value needs to be an array of the values you want to support. In your case, it has a single value which is a string containing both values (it just translates to application/xml,application/json - it will send both).
2. Your 200 response definition is invalid as it requires at least a description. However, the current definition says there's no response value (i.e., void) which makes the content type irrelevant and as such, the drop-down allowing you to choose the response type will not appear. You have to give it a schema value to have the ability to choose a content type.

[lakmali]

Thanks for the explanation.

I fixed my swagger definition as below and now drop-down appears to select the response content type.

get:
      x-auth-type: "Application & Application User"
      x-throttling-tier: Unlimited
      produces:
        - application/json
        - application/xml
      parameters:
        - name: id
          allowMultiple: false
          required: true
          type: string
          in: path
      responses:
        "200":
          schema:
            type: string
          description: test

[Joe23]

I don't think this problem is fixed. I am able to have the drop down appears, but when click the button "Try it out!", the UI has some kind of preference to application/json, over the application/xml.

I tried changes the order in the produces block and it still only accept application/json.

  /v1.0/something2:
    get:
      tags:
      - "v1.0"
      description: ""
      operationId: "getBoth"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "Accept"
        in: "header"
        required: false
        type: "string"
      responses:
        default:
          description: "successful operation"

Tested in swagger swagger-ui-2.2.8 and swagger-ui-2.2.6

[fehguy]

use this instead:

consumes:
  - application/xml

Which translates to the Accept header.

[Joe23]

Thanks for your suggestion. I update my code but looks like same things.

I notice that if I take out the application/json from the produces and only has application/xml, then application/xml in the form works. but as long as application/json is in produces, the xml won't work.

[webron]

What does your current spec look like?

[Joe23]

Here is the full spec.

---
swagger: "2.0"
info:
  version: "1.0.0"
  title: ""
host: "192.168.56.1:56489"
basePath: "/sso/"
tags:
- name: "v1.0"
schemes:
- "http"
paths:
  /v1.0/something2:
    get:
      tags:
      - "v1.0"
      operationId: "getBoth"
      consumes:
      - "application/xml"
      - "application/json"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "Accept"
        in: "header"
        required: false
        type: "string"
      responses:
        default:
          description: "successful operation"

Also, Here is the Java Class code if you are interested.

import java.util.concurrent.CompletableFuture;

import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.HeaderParam;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.container.AsyncResponse;
import javax.ws.rs.container.Suspended;
import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;

@Path("/v1.0")
@Api(value = "/v1.0",produces = MediaType.APPLICATION_JSON+","+MediaType.APPLICATION_XML)
public class Sample {
	@GET
	@Path("something2")
	@Produces({ MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON })
	@Consumes({ MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
	public void getBoth(@Suspended final AsyncResponse asyncResponse,@HeaderParam(HttpHeaders.ACCEPT) final String type) {
		CompletableFuture.runAsync(() -> {
			asyncResponse.resume("OK");
		});
	}
}

[webron]

Remove the accept header definition. You should do that from your spec, and from your code. That's simply not how you handle it in either.

[Joe23]

ehhh ... if I remove accept, then there is no place in the swagger ui to indicate that it can accept either json or xml, which defeat the purpose of API document.

Also, there is no way I can test it through the UI

[webron]

That's why you have the produces. The reason that won't render for you is that you don't describe the schema for the response. If there's no schema, the response is empty, and then.... the media type is meaningless.

[Joe23]

Thanks @webron , it is the response does the trick. For ppl visiting this thread you can add this to the function.

@ApiOperation(response = APIResponse.class, value = "sample test")

Then the swagger core will inspect the APIResponse.class to simulate the response structure and sample output.

[prativapokhrel]

I had the same issue so tried to hardcode the swagger.js file which luckily worked for me. I changed "responseContentType = application/json" to "responseContentType = value of accepts parameter". Hope it works for you as well :)

[yusufdem1r]

Hey, I had the same problem. changed name("Accept") to name("accept") and it's work me :)

@configuration
@EnableSwagger2
public class SwaggerConfig {

@Bean
public Docket api(){
    return  new Docket(DocumentationType.SWAGGER_2).globalOperationParameters(
            Arrays.asList(new ParameterBuilder()
                    .name("accept")
                    .description("Result Type: JSON(application/json)-XML(application/xml)")
                    .modelRef(new ModelRef("string"))
                    .parameterType("header")
                    .required(true)
                    .build()));
}

}